Cocodimonium hydroxypropyl hydrolysed keratin

Endpoint summary

Description of key information

Skin sensitisation - HRIPT

Based on the study results, the test substance was determined to be non skin sensitiser (CPT, 2004).

Additional information

Human Repeat Insult Patch Test (HRIPT)

A study was conducted to determine by repetitive epidermal contact the potential of a test substance, Hydrolysed keratin (Purity: Unknown) to induce primary or cumulative irritation and/or allergic contact sensitization, with compliance with ICH E6 GCP (Good Clinical Practice) and 21 CFR Part 50 and 56. Fifty eight human volunteers, male and female, ranging in age from 18 to 79 years, were selected for this evaluation (Fifty one human volunteers completed this study, while remaining subjects discontinued their participation for various reasons, none of which were related to the application of the test substance). Approximately 0.2 mL of the test substance, or an amount sufficient to cover the contact surface, was applied to the 1" x 1" absorbent pad portion of a clear adhesive dressing. This was then to the upper back between the scapulae to form a semi-occluded patch. Patches were applied three times per week for a total of nine applications. Following supervised removal and scoring of the first Induction patch, participants were instructed to remove all subsequent Induction patches at home, twenty four hours after application. The evaluation of this site was made again just prior to re-application. If a participant was unable to report for an assigned test day, one makeup day was permitted. This day was added to the Induction period. With the exception of the first supervision Induction Patch reading, if any test site exhibited a moderate (2-level) reaction during the Induction Phase, application was moved to an adjacent area. Applications are discontinued for the remainder of this test phase, if a moderate (2-level) reaction observed on this new test site. Applications would also be discontinued if marked (3- level) or severe (4-level) reactivity was noted. Rest periods consist of twenty-four hours following each Tuesday and Thursday removal, and forty-eight hours following each Saturday removal. Approximately two weeks after the final Induction patch application, a Challenge patch was applied to a Virgin test site adjacent to the original Induction patch site, following the same procedure for Induction. The patch was removed and the site scored at the clinic twenty-four and seventy-two hours post-application. Based on the grading and evaulations of study results, the study author concluded that test substance did not induce dermal irritation or allergic contact sensitization throughout the test interval. Under the study conditions, test substance did not indicate a potential for dermal irritation or allergic contact sensitization (CPT, 2004).